Pooler Cpuminer is quite an effort to run and it mines at 30Khash at i-7 3.3ghz
But as I know further some folks need to compile bfgminer with enabled cpu for it to give higher amount, as I know there are no support given in this field with cpumining.
So many of us would really like faster cpumining with bfgminer, but as far as I know pooler-cpuminer is the best out there still.
To have it run on all 8 cores just use this batch:
-q makes it quiet as for showing only accepted and staled shares.
minerd --url=stratum+tcp://poolhost.com:port --userpass=username:password --threads=8 -q